1. Field of the Invention
The present invention relates to a vehicle-mounted device communication controller, and more particularly to a vehicle-mounted device communication controller in which when operating an operation knob having a security function and operable to be pressed and rotated, a strange feeling and an easy feeling at an operation-knob operation time are removed by making the release time of the security function early.
2. Description of the Related Art
Conventionally, for vehicle-mounted device communication controllers which are used mounted in automotive vehicles, the controllers having both a passive keyless entry function and a smart-engine-starter function have been known. A vehicle-mounted device communication controller of this type is provided with a vehicle-mounted unit, and the communication using radio signals is performed between the vehicle-mounted unit and one or more portable unit to be carried by the user. The communication at this time is such that the vehicle-mounted unit sends a low-frequency radio signal of low power to each of the portable units as a search signal intermittently, when any one of the portable units receives this search signal, the received portable unit sends back a response signal, and when the vehicle-mounted unit receives this response signal, the communication is established between the vehicle-mounted unit and the portable unit. Then when the communication is established between the vehicle-mounted unit and the portable unit, the vehicle-mounted unit authenticates the portable unit, which is the communication opponent, that the portable unit is an ID registered normal portable unit. After such an authentication is performed, in the vehicle-mounted device communication controller, the passive keyless entry system changes the setting of the door-locking mechanism from a lock state to an unlock state in order to enable the user and the like to open the door freely. Also, the smart-engine-starter changes the setting of the engine start operation from a prohibited state to a release state, thereby making it possible to start the engine freely.
In this case, the communication between the vehicle-mounted unit and the portable unit continues after the settings of the passive keyless entry and the smart engine starter have been changed. By the communication thereafter, checking is performed whether the portable unit stays within a predetermined range, or the unit stays in the vehicle.
In order to achieve both functions of the passive keyless entry and the smart engine starter, a well known vehicle-mounted device communication controller performs those functions using the common portable units and by the common communication process.
However, in the vehicle-mounted device communication controller, when carrying out such a communication process, a trouble of the operation sometimes arises as described below depending on the structure of the smart engine starter.
In general, in an ignition system using a conventional mechanical key, by inserting a mechanical key into a key cylinder and by rotating the key at the position, the position of the key is changed to an ACC-ON position and to an operable position of the engine starter. However, recently, as an advanced technical means, an engine starter, in which an operation knob is pressed and then rotated to start engine using an operation knob operable to be pressed and rotated in place of an engine starter in which a mechanical key is used to be inserted in the key cylinder and rotated to start the engine, has been proposed by the applicant of the present invention. The smart engine starter having such a structure is provided with a security mechanism.
Specifically, a smart engine starter of this type has an operation knob operable to be pressed and rotated, which is connected with a rotatable ignition switch, and, in addition, includes a switch-detection mechanism which detects the pressing state of the operation knob, and a switch-operation restriction mechanism (security mechanism) which restricts and releases the rotation of the ignition switch.
FIG. 6 is a front view illustrating an example of the structure of the external appearance of the smart engine starter in the above-described proposal.
As shown in FIG. 6, this smart engine starter has an operation knob 61 connected with a rotation axis of a rotatable ignition switch (not shown in the figure), and the portion around the operation knob 61 has marks indicating a switch-off position (OFF) 62, an accessory-ON position (ACC) 63, an ignition-ON position (IGN) 64, and an engine-start position (Starter) 65.
The operation of the smart engine starter having such a structure is as follows:
The operation knob 61 can always be pressed, however, as long as the switch-restriction mechanism (not shown in the figure) maintains the restriction state, the knob cannot be rotated, and thus the operation knob 61 cannot be rotated to indicate at any one of the accessory-ON position (ACC). 63, an ignition-ON position (IGN) 64, and an engine-start position (Starter) 65. In this state, the operation knob 61 cannot be rotated, and thus the engine cannot be started.
Here, a description will be given of the operations of the vehicle-mounted device communication controller (in the following, simply described as a vehicle-mounted unit) when the user gets in the vehicle and starts the engine step by step.
The communication (in the following, this communication is referred to as a first communication) between the vehicle-mounted unit and the portable unit to be carried by the user is performed, and if the portable unit is determined as a normal portable unit by the means, the setting of the door-locking mechanism is changed to a release state, and thus the user can open the door and gets in the vehicle. At this time, when the door-opening/closure detection switch detects the opening of the door and then the subsequent closure of the door, the communication (in the following, this communication is referred to as a second communication) between the vehicle-mounted unit and the portable unit is performed again. If it is detected that the portable unit is in the vehicle by the second communication, the vehicle-mounted unit determines that the user has got in the vehicle.
Thereafter when the user presses the operation knob 61, and the switch-detection mechanism detects the pressing of the operation knob, the communication (in the following, this communication is referred to as a third communication) between the vehicle-mounted unit and the portable unit is performed by the trigger of the detection. When the third communication is established, the vehicle-mounted unit changes the setting of the switch-operation restriction mechanism from a restricted state up to that time to a release state, and releases the restriction of the rotation operation of the operation knob 61. By this means, the operation knob 61 becomes possible to be rotated freely, thus the operation knob 61 can be rotated to the engine-start position (Starter) 65 through the accessory-ON position (ACC) 63 and the ignition-ON position (IGN) 64, and thus the engine can be started by the operation of the operation knob 61.
Here, FIGS. 7 and 8 are diagrams illustrating examples of operation sequences at a first to a third communication execution time between the vehicle-mounted unit and the portable unit in the smart engine starter in the above-described proposal. FIG. 7 is an example of the case where one portable unit out of a plurality of portable units sends a response signal in response to the sending of a search signal (TID signal), FIG. 8 is an example of the case where none of a plurality of the portable units sends a response signal in response to the sending of a search signal (TID signal), and the plurality of the portable units includes the portable units A, B, and C.
As shown in FIGS. 7 and 8, when performing the first to the third communication, the vehicle-mounted unit sends, at the start of the communication, a all search signal named a all TID signal included a VID signal (Sv) indicating the start of the all search signal and the single pulses (Ta), (Tb), and (Tc) corresponding to the total number of portable units to be searched subsequently at intervals of a predetermined response-signal waiting time.
At this time, as shown in FIG. 7, when the vehicle-mounted unit sends the VID signal (Sv), the single pulse (Ta) for the portable unit A, and the single pulse (Tb) for the portable unit B in sequence, the portable unit B receives the single pulse (Tb) and sends the simple response signal (Rb) in response to it. When the vehicle-mounted unit receives the simple response signal (Rb), the unit stops sending the single pulse (Tc) thereafter, and sends the challenge signal (Ca) for the portable unit B immediately. At this time, when the portable unit B receives this challenge signal (Ca), the portable unit B sends the response signal (Rs) in response to it. When the vehicle-mounted unit receives the response signal (Rs), the vehicle-mounted unit checks the received response signal, authenticates the portable unit based on the check result, and thus the communication between the vehicle-mounted unit and the portable unit B is established. In this regard, the response signal is a signal including an ID fixed for each portable unit.
On the other hand, as shown in FIG. 8, when the vehicle-mounted unit sends the VID signal (Sv), the single pulse (Ta) for the portable unit A, the single pulse (Tb) for the portable unit B, and the single pulse (Tc) for the portable unit C in sequence, and if and the response-signal time has passed, but the response signal is not sent from any of the portable units A, B, and C, sending the search signal is stopped at that time.
In the smart engine starter proposed as described above, when the user pressed the operation knob 61 in order to start the engine, and the switch-detection mechanism detects the pressing of the operation knob 61, the vehicle-mounted unit sends the all search signal (all TID signal). In response to the sending of the single pulse (Tb) of the all search signal (all TID signal), the corresponding portable unit B sends the response signal (Rb) After the vehicle-mounted unit receives this simple response signal (Rb), the vehicle-mounted unit sends the challenge signal (Ca) to the portable unit B. The portable unit B which has received the challenge signal sends the response signal (Rs). The vehicle-mounted unit checks this response signal (Rs) and the communication between the vehicle-mounted unit and the portable unit B is established. It takes about a 200 millisecond (ms) of time for this process. Furthermore, it takes tens of milliseconds (ms) of time from the establishment of the communication to the release of the restriction of the rotation operation of the operation knob 61. The sum total of these time becomes much larger than about 200 millisecond (ms) of time.
On the other hand, in the case of performing a normal operation, the time required from the user's pressing the operation knob 61 to the rotation operation of the operation knob 61 thereafter is shorter than the above-described sum total time. Thus after the user pressed the operation knob 61, the user must wait for a short period of time until the knob becomes rotatable. Therefore the user may have a strange feeling about the operation state of the operation knob 61, may mistakenly consider that a trouble has occurred with the smart engine starter, and may have an uneasy feeling.